Showing papers on "Gasoline published in 2015"

An overview of methanol as an internal combustion engine fuel

Abstract: Methanol is an alternative, renewable, environmentally and economically attractive fuel; it is considered to be one of the most favorable fuels for conventional fossil-based fuels. Methanol has been recently used as an alternative to conventional fuels for internal combustion (IC) engines in order to satisfy some environmental and economical concerns. Because of a number of relatively large research projects that have been ongoing recently, much progress has been made that is worth reporting. This paper systematically describes the methanol productions, including the productions from coal, natural gas, coke-oven gas, hydrogen, biomass etc. It introduces the potentials of methanol as a renewable resource taking into account the world supply and demand, economic benefits and the effects on human health and the environment. Thirteen methods of application such as methanol/gasoline, methanol/diesel blends which can be used on the IC engines are summarized. Finally, this paper puts forward some new suggestions on the weakness in the researches of methanol engine.

Ignition of alkane-rich FACE gasoline fuels and their surrogate mixtures

Abstract: Petroleum derived gasoline is the most used transportation fuel for light-duty vehicles. In order to better understand gasoline combustion, this study investigated the ignition propensity of two alkane-rich FACE (Fuels for Advanced Combustion Engines) gasoline test fuels and their corresponding PRF (primary reference fuel) blend in fundamental combustion experiments. Shock tube ignition delay times were measured in two separate facilities at pressures of 10, 20, and 40 bar, temperatures from 715 to 1500 K, and two equivalence ratios. Rapid compression machine ignition delay times were measured for fuel/air mixtures at pressures of 20 and 40 bar, temperatures from 632 to 745 K, and two equivalence ratios. Detailed hydrocarbon analysis was also performed on the FACE gasoline fuels, and the results were used to formulate multi-component gasoline surrogate mixtures. Detailed chemical kinetic modeling results are presented herein to provide insights into the relevance of utilizing PRF and multi-component surrogate mixtures to reproduce the ignition behavior of the alkane-rich FACE gasoline fuels. The two FACE gasoline fuels and their corresponding PRF mixture displayed similar ignition behavior at intermediate and high temperatures, but differences were observed at low temperatures. These trends were mimicked by corresponding surrogate mixture models, except for the amount of heat release in the first stage of a two-stage ignition events, when observed.

Diesel and aviation kerosene with desired aromatics from hydroprocessing of jatropha oil over hydrogenation catalysts supported on hierarchical mesoporous SAPO-11

Abstract: Hydroprocessing of non-edible jatropha oil over sulphided NiMo and NiW catalysts supported on hierarchical mesoporous SAPO-11 was investigated under conditions of 375 − 450 °C, 60–80 bar and 1 h−1 in a fixed-bed reactor. High yield (about 84 wt%) of liquid hydrocarbon products was obtained over all the catalysts, with about 40% diesel and about 40% aviation kerosene, remaining 20% being lighter gasoline range hydrocarbons. Variation of Si content in the support (SAPO-11) did not have very significant impact on the hydroprocessing of jatropha oil. The liquid hydrocarbon products had suitable density and viscosity, and low sulphur content. The catalysts did not show any observable deactivation with time (∼6 days). It is the first report of a single catalyst based process, where the diesel fraction had desired pour point and high cetane value (>100), while the kerosene fraction not only had desired freezing point for Jet A-1 fuel (

Characterization of ambient volatile organic compounds and their sources in Beijing, before, during, and after Asia-Pacific Economic Cooperation China 2014

Abstract: . Ambient volatile organic compounds (VOCs) were measured using an online system, gas chromatography–mass spectrometry/flame ionization detector (GC-MS/FID), in Beijing, China, before, during, and after Asia-Pacific Economic Cooperation (APEC) China 2014, when stringent air quality control measures were implemented. Positive matrix factorization (PMF) was applied to identify the major VOC contributing sources and their temporal variations. The secondary organic aerosols potential (SOAP) approach was used to estimate variations of precursor source contributions to SOA formation. The average VOC mixing ratios during the three periods were 86.17, 48.28, and 72.97 ppbv, respectively. The mixing ratios of total VOC during the control period were reduced by 44 %, and the mixing ratios of acetonitrile, halocarbons, oxygenated VOCs (OVOCs), aromatics, acetylene, alkanes, and alkenes decreased by approximately 65, 62, 54, 53, 37, 36, and 23 %, respectively. The mixing ratios of all measured VOC species decreased during control, and the most affected species were chlorinated VOCs (chloroethane, 1,1-dichloroethylene, chlorobenzene). PMF analysis indicated eight major sources of ambient VOCs, and emissions from target control sources were clearly reduced during the control period. Compared with the values before control, contributions of vehicular exhaust were most reduced, followed by industrial manufacturing and solvent utilization. Reductions of these three sources were responsible for 50, 26, and 16 % of the reductions in ambient VOCs. Contributions of evaporated or liquid gasoline and industrial chemical feedstock were slightly reduced, and contributions of secondary and long-lived species were relatively stable. Due to central heating, emissions from fuel combustion kept on increasing during the whole campaign; because of weak control of liquid petroleum gas (LPG), the highest emissions of LPG occurred in the control period. Vehicle-related sources were the most important precursor sources likely responsible for the reduction in SOA formation during this campaign.

The Effect of Compression Ratio, Fuel Octane Rating, and Ethanol Content on Spark-Ignition Engine Efficiency

Abstract: Light-duty vehicles (LDVs) in the United States and elsewhere are required to meet increasingly challenging regulations on fuel economy and greenhouse gas (GHG) emissions as well as criteria pollutant emissions. New vehicle trends to improve efficiency include higher compression ratio, downsizing, turbocharging, downspeeding, and hybridization, each involving greater operation of spark-ignited (SI) engines under higher-load, knock-limited conditions. Higher octane ratings for regular-grade gasoline (with greater knock resistance) are an enabler for these technologies. This literature review discusses both fuel and engine factors affecting knock resistance and their contribution to higher engine efficiency and lower tailpipe CO2 emissions. Increasing compression ratios for future SI engines would be the primary response to a significant increase in fuel octane ratings. Existing LDVs would see more advanced spark timing and more efficient combustion phasing. Higher ethanol content is one available option for increasing the octane ratings of gasoline and would provide additional engine efficiency benefits for part and full load operation. An empirical calculation method is provided that allows estimation of expected vehicle efficiency, volumetric fuel economy, and CO2 emission benefits for future LDVs through higher compression ratios for different assumptions on fuel properties and engine types. Accurate "tank-to-wheel" estimates of this type are necessary for "well-to-wheel" analyses of increased gasoline octane ratings in the context of light duty vehicle transportation.

Long‐chain alkane production by the yeast Saccharomyces cerevisiae

Abstract: In the past decade industrial-scale production of renewable transportation biofuels has been developed as an alternative to fossil fuels, with ethanol as the most prominent biofuel and yeast as the production organism of choice. However, ethanol is a less efficient substitute fuel for heavy-duty and maritime transportation as well as aviation due to its low energy density. Therefore, new types of biofuels, such as alkanes, are being developed that can be used as drop-in fuels and can substitute gasoline, diesel, and kerosene. Here, we describe for the first time the heterologous biosynthesis of long-chain alkanes by the yeast Saccharomyces cerevisiae. We show that elimination of the hexadecenal dehydrogenase Hfdl and expression of a redox system are essential for alkane biosynthesis in yeast. Deletion of HFDI together with expression of an alkane biosynthesis pathway resulted in the production of the alkanes tridecane, pentadecane, and heptadecane. Our study provides a proof of principle for producing long-chain alkanes in the industrial workhorse S. cerevisiae, which was so far limited to bacteria. We anticipate that these findings will be a key factor for further yeast engineering to enable industrial production of alkane based drop-in biofuels, which can allow the biofuel industry to diversify beyond bioethanol.

Novel pathways for fuels and lubricants from biomass optimized using life-cycle greenhouse gas assessment

Abstract: Decarbonizing the transportation sector is critical to achieving global climate change mitigation. Although biofuels will play an important role in conventional gasoline and diesel applications, bioderived solutions are particularly important in jet fuels and lubricants, for which no other viable renewable alternatives exist. Producing compounds for jet fuel and lubricant base oil applications often requires upgrading fermentation products, such as alcohols and ketones, to reach the appropriate molecular-weight range. Ketones possess both electrophilic and nucleophilic functionality, which allows them to be used as building blocks similar to alkenes and aromatics in a petroleum refining complex. Here, we develop a method for selectively upgrading biomass-derived alkyl methyl ketones with >95% yields into trimer condensates, which can then be hydrodeoxygenated in near-quantitative yields to give a new class of cycloalkane compounds. The basic chemistry developed here can be tailored for aviation fuels as well as lubricants by changing the production strategy. We also demonstrate that a sugarcane biorefinery could use natural synergies between various routes to produce a mixture of lubricant base oils and jet fuels that achieve net life-cycle greenhouse gas savings of up to 80%.

Co-production of synthetic fuels and district heat from biomass residues, carbon dioxide and electricity: Performance and cost analysis

Abstract: Large-scale systems suitable for the production of synthetic natural gas (SNG), methanol or gasoline (MTG) are examined using a self-consistent design, simulation and cost analysis framework. Three basic production routes are considered: (1) production from biomass via gasification; (2) from carbon dioxide and electricity via water electrolysis; (3) from biomass and electricity via hybrid process combining elements from routes (1) and (2). Process designs are developed based on technologies that are either commercially available or successfully demonstrated at precommercial scale. The prospective economics of future facilities coproducing fuels and district heat are evaluated from the perspective of a synthetic fuel producer. The levelised production costs range from 18–37 €/GJ for natural gas, 21–40 €/GJ for methanol and 23–48 €/GJ for gasoline, depending on the production route. For a given end-product, the lowest costs are associated with thermochemical plant configurations, followed by hybrid and electrochemical plants.

Evaluating the Effects of Aromatics Content in Gasoline on Gaseous and Particulate Matter Emissions from SI-PFI and SIDI Vehicles.

Abstract: We assessed the emissions response of a fleet of seven light-duty gasoline vehicles for gasoline fuel aromatic content while operating over the LA92 driving cycle. The test fleet consisted of model year 2012 vehicles equipped with spark-ignition (SI) and either port fuel injection (PFI) or direct injection (DI) technology. Three gasoline fuels were blended to meet a range of total aromatics targets (15%, 25%, and 35% by volume) while holding other fuel properties relatively constant within specified ranges, and a fourth fuel was formulated to meet a 35% by volume total aromatics target but with a higher octane number. Our results showed statistically significant increases in carbon monoxide, nonmethane hydrocarbon, particulate matter (PM) mass, particle number, and black carbon emissions with increasing aromatics content for all seven vehicles tested. Only one vehicle showed a statistically significant increase in total hydrocarbon emissions. The monoaromatic hydrocarbon species that were evaluated showed...

Properties of Oxygenates Found in Upgraded Biomass Pyrolysis Oil as Components of Spark and Compression Ignition Engine Fuels

Abstract: Oxygenates present in partially hydroprocessed lignocellulosic-biomass pyrolysis oils were examined for their impact on the performance properties of gasoline and diesel. These included: methyltetrahydrofuran, 2,5-dimethylfuran (DMF), 2-hexanone, 4-methylanisole, phenol, p-cresol, 2,4-xylenol, guaiacol, 4-methylguaiacol, 4-methylacetophenone, 4-propylphenol, and 4-propylguaiacol. Literature values indicate that acute toxicity for these compounds falls within the range of the components in petroleum-derived fuels. On the basis of the available data, 4-methylanisole and by extension other methyl aryl ethers appear to be the best drop-in fuel components for gasoline because they significantly increase research octane number and slightly reduce vapor pressure without significant negative fuel property effects. A significant finding is that DMF can produce high levels of gum under oxidizing conditions. If the poor stability results observed for DMF could be addressed with a stabilizer additive or removal of im...